The analysis — referred to as “JAM20-SIDIS” — represents the most comprehensive determination of parton to hadron (\(\pi ^\pm \) , \(K^\pm \) , \(h^\pm \) ) FFs fitted concurrently with spin-averaged parton distributions, broadening the test of universality of parton correlation functions to more observables.
The more thorough exploration of the parameter space and reduced \(\chi ^2_{\rm red}\)  values for each of the \(\approx 70\)  datasets fitted in this study confirmed the previous finding [1]} that the combination of SIA and SIDIS datasets have a strong preference for a smaller strange to nonstrange PDF ratio, \(R_s\) , correlated with an enhanced \(D_{\bar{s}}^{K^+}\)  FF.
As further tests of this scenario, we plan in future to extend the experimental datasets to include weak-boson and jet production in hadronic collisions, from both Tevatron and LHC data, as well as to relax the \(W^2\)  cuts for inclusive DIS to incorporate more fixed-target DIS data at high \(x_{\mbox{\tiny \rm Bj}}\)  values [2]}.
